Eight hyphomycetes were collected as part of an investigation into the diversity of hyphomycetous fungi in China. Based on morphology and multi-loci (LSU, ITS, tef1α, and rpb2) phylogenetic analyses, five new taxa, including a new Aquapteridospora species A. hyalina and four novel Distoseptispora species, viz D. aquisubtropica, D. septata, D. tropica, and D. wuzhishanensis were introduced in Distoseptisporales (Sordariomycetes). Two new habitat records, viz Distoseptispora pachyconidia and D. xishuangbannaensis were firstly reported. Also provided in this study are detailed descriptions of eight new collections and a revised phylogenetic tree for the Distoseptisporales.

Three helicosporous hyphomycete collections representing two species were obtained from rotting wood found in freshwater and terrestrial habitats in the Guizhou and Guangxi Provinces, China. A new genus Pseudotubeufia (Tubeufiaceae, Tubeufiales), comprising Ps. hyalospora sp. nov. and Ps. laxispora sp. nov., was introduced with morphological characteristic and molecular data. In addition, the molecular evidence showed that Helicomyces sp. (G.M. 2020-09-19.1), H. roseus (CBS: 102.76), and the new genus Pseudotubeufia clustered together with high support based on a multi-gene (LSU, ITS, tef1α, and rpb2) phylogenetic analysis. Detailed descriptions, illustrations, and notes of the three new collections are provided.

Endophytic fungi are a remarkably diverse group of microorganisms that have imperceptible associations with their hosts for at least a part of their life cycle. The enormous biological diversity and the capability of producing bioactive secondary metabolites such as alkaloids, terpenoids, and polyketides have attracted the attention of different scientific communities, resulting in numerous investigations on these fungal endophytes. During our surveys of plant-root-based fungi in the mountain areas of Qingzhen, Guizhou Province, several isolates of endophytic fungi were identified. In this study, a novel endophytic fungus was discovered in the roots of a medicinal plant (Orixa japonica) in Southern China and introduced as a new species (Amphisphaeria orixae) based on morphological evidence and molecular phylogenetic analysis (combined ITS and LSU sequence data). To the best of our knowledge, A. orixae is the first reported endophyte as well as the first hyphomycetous asexual morph in Amphisphaeria. A new isocoumarin, (R)-4,6,8-trihydroxy-5-methylisochroman-1-one (1), and 12 known compounds (2–13) were isolated from the rice fermentation products of this fungus. Using 1D- and 2D-NMR, mass spectrometry, and ECD studies, their structures were identified. The antitumor activity of these compounds was tested. Unfortunately, none of the compounds tested showed significant antitumor activity.

Neohelicomyces species are a group of helicosporous hyphomycetes with the potential to produce secondary metabolites. During our investigation of helicosporous fungi, six collections were isolated from both terrestrial and freshwater habitats in Guizhou Province, China. Based on multigene phylogenetic analysis (ITS, LSU, tef1α and rpb2), coupled with morphological data, three new Neohelicomyces species, viz. N. guizhouensis, N. helicosporus and N. hydei were established. A list of accepted Neohelicomyces species with molecular data was provided. The strain of Neohelicomyces pallidus (UAMH 10535) was synonymised under N. denticulatus based on molecular data.

Helicosporous hyphomycetes is a group of filamentous fungi that shows promising application prospects in metabolizing bioactive natural compounds. During a study of helicosporous fungi in China, six new helicosporous taxa were collected and isolated from decaying wood in Guangxi Zhuang Autonomous Region, China. Morphological comparisons with multi-gene phylogenetic analyses revealed that these six taxa belong to Helicosporium (Tubeufiaceae, Tubeufiales), and they were recognized as three novel species and were named Helicosporium liuzhouense, H. multidentatum, and H. nanningense. Detailed descriptions and illustrations of the newly discovered taxa and comparisons with similar fungi are provided. In addition, a list and a key to accepted Helicosporium species are provided.

During our investigation of saprobic fungi in southwestern China, three micro-hyphomycetous fungi were isolated from dead wood in freshwater and terrestrial habitats in Guizhou Province. Phylogenetic analyses of ITS, LSU, and SSU sequences, performed using Maximum Likelihood and Bayesian Inference methods, confirmed that these isolates belong to Kirschsteiniothelia. Based on distinct morphological characteristics and molecular phylogenetic evidence, we describe three new species: Kirschsteiniothelia guizhouensis, K. weiningensis, and K. xishuiensis. Furthermore, the effectiveness of three DNA markers for species-level identification within Kirschsteiniothelia was evaluated using Assemble Species by Automatic Partitioning (ASAP) analysis, which identified the ITS nucleotide sequences as the most reliable marker for species differentiation within the genus.